This invention relates generally to balustrades, and in particular to a balustrade wherein a series of balusters are connected to a top rail or to both top and bottom rails at longitudinal spacings. The invention is more specifically directed to a prefabricated balustrade wherein the balusters and the rail or rails are both provided in standardized form, such that the balusters can be easily and positively connected to the rail or rails without use of any assembling tools or fastening elements.
Various means have been proposed and used for connection of balusters to a top or bottom rail. According to an example of such known means, a pair of opposed connectors project downwardly from each of a series of apertures formed in a bottom surface of a top rail. These connectors are inserted into each hollow baluster to be connected to the rail, and a wedge is then driven in between the connectors for rigidly joining the baluster to the rail. This method is disadvantageous in view of the difficulties involved in the production of the rail with its connectors and in the assemblage of the complete balustrade. Moreover, since the balusters are subject to constant internal pressure from the driven-in wedges, cracks or fissures tend to be produced therein during the expected lifetime of the balustrade.
Another method is known in which an end portion of each hollow baluster is cut off, and the opposed ends of the remaining baluster proper and the severed end portion are held in abutment against the surrounding edge portion of an aperture formed in the top plate of a bottom rail from the opposite sides thereof. A headed pin is then driven into and through the severed baluster end portion so as to project through the aperture into the baluster proper. This method also has a drawback in connection with the extra time and labor required for cutting off the end portion of each baluster. The possible formation of cracks or fissures in the balusters with the lapse of time is a problem in common with the precedingly described method.
According to still another example of the prior art means, a hollow, metal-made cylinder is fitted over one end of each baluster, and this cylinder is inserted into and through an aperture formed in the top plate of a bottom rail. Mechanical compressing pressure is then exerted upon the cylinder by means of a suitable tool to form bellows-like pleats therein, thereby causing the cylinder to engage the top plate of the bottom rail between the pleats and also to tightly embrace the end portion of the baluster that has been fitted therein. However, the application of pressure to the cylinder from the opposite sides of the bottom rail, in a manner well calculated to produce the anticipated results, is a highly troublesome and time-consuming operation. It is also a disadvantage of this known method than the balusters cannot necessarily be connected to the rail with a desired degree of firmness. The balustrade thus assembled, moveover, is unappealing to the eye because parts of the pleated cylinders remain exposed upon the bottom rail.